From a study by Social Security's Office of the Chief Actuary on Probability of Death While Pending an Administrative Law Judge Determination:
There are two key findings. First, the death rate for individuals who are awaiting an ALJ determination has declined somewhat over the period from 2006 to 2017. Second, the death rate for this group, while it is two to three times as high as that for the general population, is only about one-fourth of the death rate for workers who have been awarded disabled worker benefits and are in their first two years of benefit entitlement. ...
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The summary given above is accurate but I don't see why anyone would find this report reassuring. There are far too many people waiting for hearings and thousands of them die each year.
To give a full report on this issue shouldn't the Office of Chief Actuary have looked at what happened to those disability claims after the claimants died? The vast majority of those cases didn't die with the claimant. Someone was entitled to whatever benefits accrued before the claimant's death. Sure, some of those claims were denied but I'm pretty sure that the vast majority of those claims were approved after the claimant died. Isn't that an important?